"Could it be your hand after all?": I think it's more likely that they bid 7NT (kinda a fashion these days) than we ever play anything not doubled. I'll refrain from going deeper in what one should and shouldn't do if they actually bit it (the NT ...

As a rule, I always credit the tomatoes to the one that started it. Now, if the mistake was something like a LA (maybe close to it), I would gladly look at the rest of the auction, but this here 2NT hit me too hard.